1. Technical Field
The present invention relates to a voltage division circuit, in particular, to a multi-stage voltage division circuit having voltage division elements connected in parallel with each other.
2. Description of Related Art
In integrated circuits, voltage division circuits are used for generating different voltages to loads, so as to drive the loads or providing for loads doing other applications.
The traditional voltage division circuit is configured for voltage division elements connected in series in the same current path to generate divided voltages accordingly. The following regards the voltage division element as the resistor, as shown in FIG. 1. The voltage division circuit 10 is configured for four resistors R1, R2, R3, and R4, which are connected in series in a current path IC. The resistors R1˜R4 have the same resistance value. One end of the voltage division circuit 10 receives the voltage VC and another end connects to ground. Therefore, the voltage division circuit 10 respectively generates the divided voltages B1, B2, and B3 among the resistors R1˜R4 according to the resistance value of the resistors R1˜R4. Meanwhile, the voltages Vn of the divided voltages B1, B2, and B3 are defined by Vn=n/4*VC, wherein n is an integer from 1˜3. The input powers Pn of the divided voltages B1, B2, and B3 are defined by Pn=Vn*IC, wherein n is an integer from 1˜3.
However, the higher driving capability each divided voltage B1˜B3 has, the greater static power the voltage division circuit 10 has. Moreover, each divided voltage B1˜B3 has power consumption calculated by Pn=Vn*IC, causing lower driving efficiency of the voltage division circuit 10. In addition, the relation among the divided voltages B1˜B3 is higher in the structure of the resistors connected in series. When the load connected to one divided voltage is changed, the other divided voltages may also be affected by the changed load, causing worse stability of the divided voltages B1˜B3. Therefore, if the abovementioned drawback may be improved, the voltage division circuit 10 may generate more stable divided voltages B1˜B3 to the corresponding loads.
To address the above issues, the inventor strives via associated experience and research to present the instant disclosure, which can effectively improve the limitation described above.